TISSUES AND ORGANS. 5 



pearance, by which it can be recognized with the micro- 

 scope, and some one or more distinctive properties which 

 fit it for some special use ; thus, it may be very tough, and 

 suited for binding other parts together ; or rigid, and 

 adapted to preserve the shape of the body ; or have the 

 power of changing its length and be useful for moving 

 parts to which its ends are attached. 



The tissues are variously combined to form the organs 

 of the body, of which there are very many, differing in size, 

 shape, and structure ; some organs contain only a few tis- 

 sues ; others, a great many ; some possess only tissues 

 which are found also in other organs, others contain one 

 or more tissues peculiar to themselves ; but wherever an 

 organ is found, it is constructed and placed with reference 

 to the performance of some duty ; the organs are the ma- 

 chines which are found in the factory represented by the 

 body, and the tissues are the materials used in building 

 the machines; or, using another illustration, we may, with 

 Longfellow, compare the body to a dwelling-house ; and 

 then go on to liken the tissues to the brick, stone, mortar, 

 wood, iron, and glass, used in building it ; and the organs 

 to the walls, floors, ceilings, doors, and windows, which, 

 made by combining the primary building materials in 

 different ways, have each a purpose of their own, and all 

 together make the house. 



How are tissues recognized ? Give examples of differences in 

 properties of various tissues. 



How do organs differ from one another ? In what do all organs 

 agree ? Illustrate the relation of organs and tissues to the body as a 

 whole ? 



connective tissue. 4. Yellow elastic tissue. 5. Glandular tissue, of which there are 

 many varieties. 6. Respiratory tissues. 7. Fatty tissue. 8. Sense-organ or irritable 

 tissues. 9. Nerve cell tissue. 10. Nerve fiber tissue. 11. Striped muscular tissue. 

 13. Uustriped muscular tissue. 13. Epidermic and epithelial tissue. 



